# How to Create a Custom Sign-Up Screen for Your FlutterFlow App

- Tool: FlutterFlow
- Difficulty: Beginner
- Time required: 20-30 min
- Compatibility: FlutterFlow Free+
- Last updated: March 2026

## TL;DR

Build a registration page with name, email, password (with a real-time strength meter using LinearPercentIndicator), confirm password, and a TOS agreement checkbox. The sign-up action flow creates the Firebase Auth account first, then writes a user document to Firestore with displayName, email, and createdAt. A Custom Function calculates password strength by checking length, uppercase, number, and special character — returning a 0.0 to 1.0 score that colors the progress bar red, orange, or green. After sign-up, send a verification email.

## Building a Registration Page with Password Strength Meter and Email Verification in FlutterFlow

A good sign-up screen balances security with usability. This tutorial builds a registration form with real-time password strength feedback, terms agreement enforcement, and a two-step creation flow (Auth account first, then Firestore user document) to prevent orphaned data.

## Before you start

- A FlutterFlow project with Firebase Authentication and Firestore configured
- Email/Password sign-in method enabled in Firebase console
- A users collection in Firestore for storing user profile data
- A Terms of Service page already created for linking

## Step-by-step guide

### 1. Build the registration form with name, email, password, and confirm password TextFields

Create a SignUpPage with a SingleChildScrollView containing a Column (padding: 24). Add: Text 'Create Account' (headlineMedium, bold), SizedBox(24), TextField 'Full Name' (prefixIcon: person, textCapitalization: words), SizedBox(16), TextField 'Email' (prefixIcon: email, keyboardType: emailAddress), SizedBox(16), TextField 'Password' (prefixIcon: lock, obscureText with visibility toggle suffix, hintText: 'At least 8 characters'), SizedBox(8) — the strength meter goes here (next step), SizedBox(16), TextField 'Confirm Password' (prefixIcon: lock_outline, obscureText). Create Page State variables for all four field values plus isPasswordVisible (Boolean).

**Expected result:** The sign-up form shows four labeled TextFields with proper keyboard types and a password visibility toggle.

### 2. Create a passwordStrength Custom Function and bind it to a LinearPercentIndicator

Create a Custom Function passwordStrength(String password) that returns a double from 0.0 to 1.0. Logic: start with score 0.0. Add 0.25 if password.length >= 8. Add 0.25 if password contains an uppercase letter (RegExp r'[A-Z]'). Add 0.25 if password contains a digit (RegExp r'[0-9]'). Add 0.25 if password contains a special character (RegExp r'[!@#$%^&*]'). Return the score. Below the password TextField, add a LinearPercentIndicator (lineHeight: 6, percent: bound to passwordStrength(passwordValue), backgroundColor: grey200). Set progressColor conditionally: red if score < 0.5, orange if < 0.75, green if >= 0.75. Below the bar, add a Text showing 'Weak', 'Medium', or 'Strong' with matching color.

**Expected result:** As the user types their password, the strength bar fills and changes color from red to orange to green in real time.

### 3. Add the TOS checkbox with tappable Terms and Privacy links

Below the confirm password field, add a Row: Checkbox bound to Page State tosAccepted (Boolean) + RichText with plain text 'I agree to the ' + tappable TextSpan 'Terms of Service' (underline, primary color, On Tap → Navigate to TOS page) + plain text ' and ' + tappable TextSpan 'Privacy Policy' (underline, primary color, On Tap → Navigate to Privacy page). The Create Account Button below should be disabled (Conditional property: enabled = tosAccepted && all fields non-empty && password == confirmPassword).

**Expected result:** The checkbox must be checked and all fields valid before the Create Account button becomes active. Terms and Privacy links navigate to their respective pages.

### 4. Implement the sign-up action: create Auth account first, then Firestore user document

On the Create Account Button tap: (1) Validate — email format, password length >= 8, password == confirmPassword, tosAccepted is true. Show SnackBar for any failure. (2) Call Firebase Auth Create Account (email, password). (3) On Auth success, immediately Create Document in users collection: uid (currentUser.uid), displayName (nameValue), email (emailValue), photoUrl (''), createdAt (Timestamp.now()), tosAccepted (true), tosAcceptedAt (Timestamp.now()). (4) On Firestore success → Send Email Verification (Firebase Auth action). (5) Navigate to HomePage with Replace Route. Creating Auth first prevents orphaned Firestore documents if the email is already taken.

**Expected result:** Sign-up creates the Auth account, writes the user profile to Firestore, sends a verification email, and navigates to home.

### 5. Handle Firebase Auth errors for duplicate email, weak password, and invalid email

On the Auth Create Account failure branch, add Conditional Actions: if error code contains 'email-already-in-use' → Show SnackBar 'An account with this email already exists. Try logging in.' If 'weak-password' → Show SnackBar 'Password is too weak. Use at least 8 characters with uppercase, numbers, and special characters.' If 'invalid-email' → Show SnackBar 'Please enter a valid email address.' Default → Show SnackBar 'Sign-up failed. Please try again.' All error SnackBars use red background. Also add a try-catch around the Firestore Create Document — if it fails, delete the Auth account to avoid an auth-only orphan.

**Expected result:** Each sign-up error shows a specific, helpful message. If Firestore write fails after Auth creation, the Auth account is cleaned up.

## Complete code example

File: `FlutterFlow Sign-Up Screen Setup`

```text
PAGE: SignUpPage
  Page State: nameValue, emailValue, passwordValue, confirmPasswordValue (String)
                isPasswordVisible (Boolean), tosAccepted (Boolean)

WIDGET TREE:
  Scaffold
    SingleChildScrollView
      Column (padding: 24, crossAxisAlignment: stretch)
        ├── Text "Create Account" (headlineMedium, bold)
        ├── Text "Sign up to get started" (bodyMedium, grey)
        ├── SizedBox (24)
        ├── TextField "Full Name"
        │     prefixIcon: person, textCapitalization: words
        │     On Changed → set nameValue
        ├── SizedBox (16)
        ├── TextField "Email"
        │     prefixIcon: email, keyboardType: emailAddress
        │     On Changed → set emailValue
        ├── SizedBox (16)
        ├── TextField "Password"
        │     prefixIcon: lock
        │     obscureText: !isPasswordVisible
        │     suffixIcon: visibility toggle
        │     hintText: "At least 8 characters"
        │     On Changed → set passwordValue
        ├── SizedBox (8)
        ├── LinearPercentIndicator
        │     lineHeight: 6, borderRadius: 3
        │     percent: passwordStrength(passwordValue)
        │     progressColor: red (<0.5) | orange (<0.75) | green (>=0.75)
        │     backgroundColor: grey200
        ├── Text ("Weak" | "Medium" | "Strong", bodySmall, matching color)
        ├── SizedBox (16)
        ├── TextField "Confirm Password"
        │     prefixIcon: lock_outline, obscureText: true
        │     On Changed → set confirmPasswordValue
        ├── SizedBox (16)
        ├── Row
        │     ├── Checkbox (tosAccepted)
        │     └── RichText
        │           "I agree to the "
        │           [Terms of Service] (tappable, underline, primary)
        │           " and "
        │           [Privacy Policy] (tappable, underline, primary)
        ├── SizedBox (24)
        ├── Button "Create Account" (full width, primary)
        │     Enabled: tosAccepted && all fields valid && password == confirmPassword
        │     On Tap:
        │       1. Validate fields
        │       2. Auth Create Account (email, password)
        │       3. Create Document users/{uid} (displayName, email, createdAt, tosAccepted)
        │       4. Send Email Verification
        │       5. Navigate HomePage (Replace Route)
        │     On Failure → error-specific SnackBar
        ├── SizedBox (16)
        └── Row (center)
              ├── Text "Already have an account?"
              └── TextButton "Log In" → Navigate LoginPage

CUSTOM FUNCTION passwordStrength(String password) → double:
  score = 0.0
  if (password.length >= 8) score += 0.25
  if (RegExp(r'[A-Z]').hasMatch(password)) score += 0.25
  if (RegExp(r'[0-9]').hasMatch(password)) score += 0.25
  if (RegExp(r'[!@#$%^&*]').hasMatch(password)) score += 0.25
  return score
```

## Common mistakes

- **Creating the Firestore user document before creating the Firebase Auth account** — If Auth creation fails (e.g., email-already-in-use), you end up with an orphaned Firestore document that has no corresponding Auth account. Fix: Always create the Auth account first. Only write the Firestore user document after Auth succeeds. If the Firestore write fails, delete the Auth account to clean up.
- **Not disabling the Create Account button until the TOS checkbox is checked** — Users can submit the form without agreeing to terms, creating potential legal liability. Or worse, the action flow fails silently. Fix: Use a Conditional property on the Button: enabled = tosAccepted && passwordValue == confirmPasswordValue && all fields non-empty.
- **Checking password strength only on submit instead of in real time** — Users type their entire password, submit, get rejected for weak password, and must start over. Poor user experience. Fix: Bind the LinearPercentIndicator to passwordStrength(passwordValue) which recalculates on every keystroke via On Changed, giving instant visual feedback.

## Best practices

- Create the Auth account before the Firestore document to prevent orphaned data on failure
- Show password strength in real time with a color-coded progress bar so users fix issues as they type
- Require the TOS checkbox and disable the submit button until all validations pass
- Send email verification immediately after account creation to confirm the email address
- Use SingleChildScrollView on the form page to handle keyboard overflow on small screens
- Pre-validate confirm password match before submitting to avoid unnecessary Auth API calls
- Link Terms and Privacy as tappable RichText spans so users can read them before agreeing

## Frequently asked questions

### How does the password strength meter calculate the score?

The Custom Function checks four criteria: length >= 8 characters, contains uppercase letter, contains digit, and contains special character. Each adds 0.25 to the score, giving a range of 0.0 (none met) to 1.0 (all met).

### What happens if the Firestore document creation fails after Auth account creation?

You should catch the Firestore error and delete the just-created Auth account with currentUser.delete() to avoid an auth-only orphan. Then show an error SnackBar asking the user to try again.

### Can I add a profile photo upload during registration?

Yes. Add an optional step after the main form: show a CircleImage placeholder with a camera IconButton overlay. On tap, use Upload Media → Firebase Storage → save the URL in the user document's photoUrl field.

### How do I enforce email verification before allowing app access?

After login, check currentUser.emailVerified. If false, navigate to an EmailVerificationPage that displays a message and a Resend button. Block access to the main app until verified.

### Can I add multi-step registration with a progress indicator?

Yes. Use a PageView with Step 1 (credentials) and Step 2 (profile info like avatar and bio). Add a LinearPercentIndicator at the top showing step 1 of 2 / step 2 of 2.

### Can RapidDev help build an advanced onboarding and auth system?

Yes. RapidDev can implement multi-step registration, social auth, phone verification, role-based access, invite-only signups, and KYC identity verification workflows.

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Source: https://www.rapidevelopers.com/flutterflow-tutorials/how-to-create-a-custom-sign-up-screen-for-your-flutterflow-app
© RapidDev — https://www.rapidevelopers.com/flutterflow-tutorials/how-to-create-a-custom-sign-up-screen-for-your-flutterflow-app